n = int(input())
line = input()
rules = 5
numbers = set("0123456789")
lower_case = set("abcdefghijklmnopqrstuvwxyz")
upper_case = set("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
special_characters = set("!@#$%^&*()-+")
count_number = 0
count_lower_case = 0
count_upper_case = 0
count_special_characters = 0
for i in range(n):
    if count_number == 0 and line[i] in numbers:
        rules -= 1
        count_number += 1
    if count_lower_case == 0 and line[i] in lower_case:
        rules -= 1
        count_lower_case += 1
    if count_upper_case == 0 and line[i] in upper_case:
        rules -= 1
        count_upper_case += 1
    if count_special_characters == 0 and line[i] in special_characters:
        rules -= 1
        count_special_characters += 1
if n >= 6:
    rules -= 1
    print(rules)
else:
    if (rules + n) - 1 >= 6:
        print(rules - 1)
    elif (rules - 1) + n >= 6:
        print(rules - 1)
    else:
        rules -= 1
        print(rules + (6 - (rules + n)))